\chapter{面积、勾股定理}

\section{面积}
\input{units/czjh1-ch5-subsec1}
\input{units/czjh1-ch5-subsec2}
\input{units/czjh1-ch5-xiti17}

\section{勾股定理}
\input{units/czjh1-ch5-subsec3}
\input{units/czjh1-ch5-subsec4}
\input{units/czjh1-ch5-xiti18}

\input{units/czjh1-ch5-xiaojie}
\input{units/czjh1-ch5-fuxi}

